As a first step I'd roll back your drivers to see how it works. If it works then, you know it's at least linked to the update. If there are still issue, well then there's more digging to be done. This is a custom firmware after all and there's bound to be random issues that popup like this that cannot been forseen. Try the rollback first and see what happens. If it still does it, update back to current and then try reflashing your iHAS as a second course of action.

ALWAYS FLASH TO STOCK BEFORE ACCEPTING DASHBOARD UPDATES!!

I will not give you "workaround" solutions. Do it right, or don't do it at all!

I did another run with the same settings: Synchronising Cache...
I completely uninstalled all AMD/ATI Software: Synchronising Cache...
Now I removed the AHCI and Raid driver from the Windows Device Manager: Synchonising Cache...

I did another run with the same settings: Synchronising Cache...
I completely uninstalled all AMD/ATI Software: Synchronising Cache...
Now I removed the AHCI and Raid driver from the Windows Device Manager: Synchonising Cache...

I hope the reflash of the iHas drive will fix that :\

A reflash didn't fix it. It had something to do with the AMD drivers lingering on the system. As the registry was cleansed of all the drivers and AMD Uninstaller didnt show anything else left. It still didn't work.

I reinstalled Windows 7 and now its working totally fine again.
All I have to sacrifice is some SSD speed (4k) but its not that significant, I guess I can live with that.